Parliament Watchdog Says Intelligence-Gathering Agency Didn't Break Law When It Used NSA Surveillance Program

LONDON—Britain's intelligence-gathering agency didn't break U.K. law when it used the U.S. National Security Agency's data-surveillance program, parliament's security watchdog ruled Wednesday.

The Intelligence and Security Committee launched its investigation following allegations the Government Communications Headquarters, or GCHQ, violated the rights of U.K. citizens by accessing intelligence gathered by NSA's Internet surveillance program, called Prism, without proper authorization. The allegations were made by the...